Aug 28, 2014 3:02 PM by Associated Press
DEATH VALLEY NATIONAL PARK, Calif. (AP) - For years scientists have theorized about how large rocks - some weighing hundreds of pounds - zigzag across Racetrack Playa in Death Valley National Park, leaving long trails etched in the earth.
Now two researchers at the Scripps Institution of Oceanography have photographed these "sailing rocks" being blown by light winds across the former lake bed.
Cousins Richard Norris and James Norris say the movement is made possible when ice sheets that form after rare overnight rains melt in the rising sun, making the hard ground muddy and slick.
The phenomenon doesn't happen often because it rarely rains in the notoriously dry desert valley.
Their report says the rocks move very slowly - only about 15 feet per minute.
The findings were published Wednesday in the online journal PLOS ONE.
(Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)
PLEASE HELP US MODERATE COMMENTS
Offensive or inappropriate comments are subject to removal. To report a comment, please e-mail us at firstname.lastname@example.org, and include the name of the story and information on the comment.
Thank you! KSBY.com
20 hours ago